Mechanical tuner for string instruments

ABSTRACT

The invention relates to a mechanical tuner for stringed instruments which permits student players to rapidly tune and retune their instruments and is characterized by the tuner forming a part of the instrument during playing and being mounted in series with the string.

United States Patent Itzler-et al.

1151 3,667,336 .1451 June6, 19 72 [54} MECHANICAL TUNER FOR STRING INSTRUMENTS [72] Inventors: Sidney ltzler; Robert G. Towle, both of 1,1 13,390 10/1914 Wenzel-Schmidt ..84/455 2,130,248 9/1938 Peate ...84l297 R 2,514,835 7/1950 Bredice ..84/297 R FOREIGN PATENTS OR APPLICATIONS 140,293 4/1903 Germany ..84/455 Primary ExamineF-Stephen J. Tomsky Assistant Examiner-John F. Gonzales Attorney-Aaron. B. Karas [571 ABSTRACT The invention relates to a mechanical tuner for stringed instruments which permits student players to rapidly tune and retune their instruments and is characterized by the tuner forming a part of the instrument during playing and being mounted in series with the string.

4 Clains, 4 Drawing Figures 51 m0 ..c10d3/00,G10 7/o2 58 Field ofSearch ..s4/ 297, 454, 455,453

[56] References Cited 1 UNITED STATES PATENTS 936,624 10/1909 Hale s t/297R PATENTEnJun 6 m2 3. 667. 336

FIG; 4

MECHANICAL TUNER FOR STRING INSTRUIVIENTS THE INVENTION ments in beginning classes of students can be very time consuming and difiicult. This can be particularly true in large classes of-as many as 30-70 students where an entire orchestra may be practicing. In such cases, because of the noise of the instruments, a teacher can spend an entire 45 minutes period tuning the string instruments if an attempt is made to perfectly tune all the instruments. As students must learn correct pitch, an improperly tuned instruments is not a satisfactory teaching tool.

Accordingly, it is an object of the present invention to provide a mechanical device which will allow rapid tuning of a string instrument by the untrained or partially trained student.

It is another object of the present invention to provide a device which will pennit accurate re-tuning of a string musical instrument once it has been properly set.

Another object of the present invention is to provide a tuning device which is simple in construction and inexpensive.

Other objects of the present invention will become apparent on a further reading of the specification.

In the drawings:

FIG. 1 is a perspective view showing the tuner of the present invention as applied to a string instrument. Only one string being shown to simplify the drawing; ii FIG. 2 is a side elevational view showing the tuner as applied to a single string, I I "FIG. 3 is an exploded view of the several elements compris ing the tuner of FIG. I and 2; v

FIG. 4 is a longitudinal cross sectional view of FIG. 2.

Referring to FIG. 1 and 2 of the drawing, a tuner embodying thepre sent invention is shown in series with the string 11 of a string instrument, said tuner 10 being attached to string 1 l at one end and fine tuner hook 12 at the other end.

Referring to FIG. 3 and FIG. 4, it will be seen that tuner 10 is comprised of tuner body 13, tuner lower end cap 18, piston 20, piston rod 21, piston spring 23, spacer 24 and limiting nut 26. Tuner body 13 has a threaded inner wall 14 at one end thereof, an internal shoulder projection 15 at the mid-section thereof, said tuner body 13 having an axialbore 16 through its center extending from intemal' shoulder projection 15 to tuner body end 17 which has a beveled face. Lower end cap 18 has hook 19 fastened to one face and is threaded on its edge and is adapted to fit the internal threads of inner wall 14 of tuner body 13. Piston 20 has afiixed thereto piston rod 21, said piston rod 21 having its unattached end threaded with eye 22 located therein. Piston spring 23 is a coil spring which loosely encircles piston rod 21. One end of spring 23 rests on piston 20 and the other end on inner shoulder 15 of tuner body 13. Spacer 24 has a beveled face 31 which when in appropriate position permits the surfaces of tuner body end 17 to contact those of face 31 of spacer 24 and create a tight fit. Spacer 24 has an axial bore 25, said bore being of a diameter sufficiently large for piston rod 21 to pass through,

Limiting nut 26 has a threaded axial bore 27 of proper dimension and thread size to permit it to be threaded onto the threaded end of piston rod 21.

In operation assembled tuner 10 is placed in series with string 11 of the instrument so that hook 19 attaches to one end of the string and eye 22 is attached to fine tuner hook 12 or in a similar manner, attached to the tail piece of the instrument.

When string 11 is tightened by turning the tuning peg (not shown) or the fine tuning knob (not shown), piston spring 23 is compressed as lower end cap 18 attached to tuner body 13 is drawn toward the peg by the pull of string 1 1 or piston 20 attached to the tail piece of the instrument through piston rod 21 and eye 22'is drawn toward the tail piece by fine tuner When the correct pitch for string 1 1 is obtained, tuner 10 is set by positioning spacer 24 so that upper indicator 30 is positioned between lower indicator 29 and 29a and limiting nut 26 is then tightened. The proper positioning of spacer 24 should be accomplished by adjusting limiting nut 26 so that spacer 24 has a limited rotation with indicator 30 moving between stationary indicators 29 and 29a but starting at a perfectly aligned point of indicators 30 and 29 (or 29a).

String 1] is drawn to the proper tension by positioning spacer 24 so that upper indicator 30 can move enough to align accurately with indicator 29 or (29a). Excessive tension on string 11 will result in excessive separation between beveled end 17 of tuner body 13 and beveled end 31 of spacer 24 thereby pemiitting upper indicator 30 to move beyond the limits defined by lower indicators 29 and 29a. Insufiicient tension on string 1 1 will permit spacer 24 to contact beveled end 17 of tuner body 13 and prevent any movement of upper indicator 30.

While it is not critical to the invention, it is preferred that beveled end 17 of tuner body 13 should have a pitch of about 3 across the diameter of tuner body 13 in order to permit the desired movement of spacer body 24. If the pitch is less than about 3, the amount of free movement is reduced for a given spring tension and if the pitch is greater than about 3, a greater amount of free movement is provided. The face of spacer 24 which is in proximate relationship to beveled end 17 of tuner body 13 should also have the same pitch in the 0pposite direction to purposely block 360 rotational clearance of spacer 24 when the following conditions obtain:

1. spring 23 pushes body 13 in the direction of spacer 24 along piston rod 21; and

2. spacer 24 is confined on its other side by limiting nut 26 and has a small amount of sidewise play along piston rod 21 (a few thousandths of an inch).

As the'string is tightened by peg (not shown), body 13 is pulled away from spacer 24 while piston 20 and piston rod 21 being anchored to tuner hook 12 by piston rod eye 22 remain stationary. As a result, spring 23 is compressed and more unoccupied sideways room results on piston rod 21 allowing an excess amount of play for spacer 24 with consequent greater freedom of indicator 30 movement beyond the limits of stationary indicators 29 and 29a. Less self-blocking of beveled end 17 and beveled face 31 occurs because of the addition of sidewise room on piston rod 21. There is an interchange of anchor point and moving end of string 1 1 if fine tuner screw is used instead of peg with exactly the same effect (fine tuner screw is shown on FIG. 2 as part of hook 12 assembly). I

Loosening of string 11 creates the opposite effect because relaxation of spring 23 pushes body 13 closer to spacer 24,

' reduces sidewise movement of spacer 24 along piston rod 21 hook 12. Piston spring 23 is compressed by inner shoulder 15 pushing on piston spring 23, while piston 20 restrains the opposite end and prevents movement in the same direction.

and consequently creates more blocking of the beveled faces 17 and 31. The rotational movement of spacer 24 is now reduced as shown by a more restricted movement of indicator 30 with reference to stationary indicator 29 and 29a. Overreduction of string 1 1 tension will allow spring 23 expansion to push body 13 along piston rod 21 to excess, eliminating all possible sideways movement of spacer 24 along pistion rod 21 and will compress the two beveled faces together preventing all rotational movement of spacer 24 as shown by a complete restriction of indicator 30 movement.

The tension of a tuned string can be calibrated by positioning limiting nut 26 close to spacer 24 allowing just enough sidewise play (a few thousandths of an inch) along piston rod 21 to permit a somewhat confined rotational movement of spacer 24 as shown by the movement of indicator 30 between stationary indicators 29 and 29a. If for any reason string tension is changed and correct pitch lost, it can be regained by properly adjusting fine tuner screw, and/or peg to the previously calibrated point of correct pitch that will be shown by indicators.

A very exact calibration can be made by determining an exact starting place for the free rotational movement of ,in-

dicator 30; that can be a point where indicator 30 and 29 (or 290) line up precisely to begin the rotation. In operation, starting at that point should take precedence over whether the other end of the rotational movement reaches or goes beyond the second stationary indicator line. This reference point should be the same for setting up the calibration as for tuning by the novice. The limiting nut 26 can be repositioned when replacement strings of a different gauge or manufacture create a different set of mechanical factors. Where the tuner is used for tuning violins, it has been found desirable that piston spring 23 have an approximate rate of l9 lb./inch and a free length of about seven-sixteenths inches. Springs which have been found suitable for such purposes are stainless steel or cadmium plated compression springs such as LC-042C-l or LC-042C-2 manufactured by Lee Spring Company, Inc, 30 Main Street, Brooklyn, N.Y. 11 g01. 1 1 s beenfound generally that any combination of springs may be used for the various units provided the rate of the spring in each tuning unit is sufficient to function under the load applied by the particular string. In the case of use on violins, it has been found most preferred to use cadmium plated springs of the type described above of seven-sixteenth inches in free length.

As is well-known to those skilled in the art, the windings on strings tend to separate and rupture with use because of exces' sive friction due to pressure against the bridge at the point of contact. To reduce friction and wear and at the same time permit the spring in the tuning device to register accurately, it has been found that preferable to the usual wooden bridge, one with a case hardened and highly polished steel surface applied to the top of the bridge where contact is made with the strings should be used.

The tuner of each string can be reset to make accommodation to the relatively fixed pitch of another instrument such as the piano or organ. The following method can be used by a teacher or skilled musician. After all the strings are set about 'a half pitch below the desired sounds, proceed to tune each string in succession from the highest to the lowest. After achieving the correct pitch on the first string the limiting nut 26 of tuner 10 is turned appropriately to allow a rotation of spacer 24 just wide enough to be able to begin movement where indicators 30 and 29 (or 290) coincide. Accurate pitch is tested by retuning the string using the fine tuner to set it slightly below pitch and to reset it up to correct pitch. The

remaining strings are set in the same manner without, however, lowering any of the strings already set. A test tuning by using indicators 30 and 29 (or 29a) rather than by car should detennine the accuracy of settings for the novice. Any inaccuracies at this point should be corrected by ear and spacer 24 readjusted with limiting nut 26 appropriately determining the movement of spacer 24. The movement of indicator 30 must be just wide enough to allow an exact line up with indicator 29 (or 29a) when the string is in perfect tune.

What is claimed is:

1. A tuner for stringed instruments of the type having a body, at least one string to be tuned, spaced supports suspending the strings and means for adjusting the tension in said strings which comprises:

a. a tuner body with hook means at one end thereof to operably connect said body to said string, said tuner body having an internal recessed shoulder and an axial bore;

b. piston means located within said tuner body and having a piston and a piston rod, said piston rod adapted to operably slide within said axial bore of said tuner body projecting beyond said body being threaded and having an eye therein adapted to connect to tension means on said stringed instrument.

c. A piston spring located within said tuner body and having one end thereof in proximate relationship to said internal recessed shoulder of said tuner body and the other end in contact with said piston and being slidably mounted on said piston rod;

. a spacer having an axial bore operably connected to said tuner body by said piston rod passing through said axial bore; and

e. a limiting nut having an axial bore operably connected to said spacer by said piston rod passing through said axial bore.

2. A tuner according to claim 1 wherein said tuner body has an end cap threadably fastened thereto at one end, said hook means being fastened to the outside face of said end cap.

3. A tuner according to claim 2 wherein said piston spring has an approximate rate of 19 pounds per inch and a free length of about seven-sixteenths inch.

4. A tuner according to claim 2 wherein the matching faces of said tuner body and said spacer in proximate relationship to each other have a 3 bevel across the diameter. 

1. A tuner for stringed instruments of the type having a body, at least one string to be tuned, spaced supports suspending the strings and means for adjusting the tension in said strings which comprises: a. a tuner body with hook means at one end thereof to operably connect said body to said string, said tuner body having an internal recessed shoulder and an axial bore; b. piston means located within said tuner body and having a piston and a piston rod, said piston rod adapted to operably slide within said axial bore of said tuner body projecting beyond said body being threaded and having an eye therein adapted to connect to tension means on said stringed instrument. c. A piston spring located within said tuner body and having one end thereof in proximate relationship to said internal recessed shoulder of said tuner body and the other end in contact with said piston and being slidably mounted on said piston rod; d. a spacer having an axial bore operably connected to said tuner body by said piston rod passing through said axial bore; and e. a limiting nut having an axial bore operably connected to said spacer by said piston rod passing through said axial bore.
 2. A tuner according to claim 1 wherein said tuner body has an end cap threadably fastened thereto at one end, said hook means being fastened to the outside face of said end cap.
 3. A tuner according to claim 2 wherein said piston spring has an approximate rate of 19 pounds per inch and a free length of about seven-sixteenths inch.
 4. A tuner according to claim 2 wherein the matching faces of said tuner body and said spacer in proximate relationship to each other have a 3* bevel across the diameter. 